There is a confirmed bug with compilations, that's probably it. If the artist is not he album artist then the application fails to show any results.
I will start working on a fix hopefully by the end of the week.
The only thing affected by the size of the library is the time that it will takes to sync the library metadata.
Thanks for getting back to me. That was the problem. I reset the tags for the album artist and artist to be the same and they showed up on the remote library on my tablet!
One more suggestion: For people with very large libraries, it takes forever to scroll down to the end of the artist list. Perhaps there would be a way to put a slider on the right to scroll down more quickly.
Thanks again for your work on this. It is a great app!